Snow in Summer Temperature

Rising average temperatures in the winter months result in an increasing lack of snow even in high-altitude winter sports areas. This presents competition organizers and ski slope operators with a logistical and economic challenge. Artificial snow is often needed for the trails to be safe and fun for recreational athletes, and for ski clubs and organizers to hold competitions under normal conditions.

Refrigeration specialist KTI-Plersch Kältetechnik GmbH from Balzheim, Germany, has more than 35 years of experience developing various refrigeration systems. It now offers snowPRO, a container-sized mobile solution, which ensures crisp, white cross-country ski runs and slopes even at warm temperatures and regardless of weather conditions. This snow stays in place longer and is not negatively affected by climate or wind as it contains more energy and is more compact than snow from conventional snow cannons. This enables effective snowmaking on the slopes.

When Felix Neureuther won the World Cup parallel slalom on Munich’s Olympiaberg on New Year’s Day 2013 against the impressive backdrop of the Olympic Park, it was clear that regularly staging the race in the middle of the Bavarian capital would not be easy. However, nobody expected the second slalom held there would also be the last due to lack of snow. In 2015, the German Ski Association decided to end the competition.

However, since then it has not just been event organizers in Munich or piste operators in the foothills of the Alps for whom the lack of snow has been a headache. Anyone who regularly hits the ski slopes in the cold months or follows snowsports – whether biathlon, cross-country skiing, Nordic combined, ski jumping or even alpine races – will have noticed that in many places the dreamy white backdrop has given way to slushy white strips of snow surrounded by green-brown landscapes.

In recent years, there has also been an increase in reports of international competitions in various disciplines moving to other venues, or even cancelled altogether, because the essential white element was missing, or it has not been possible to stage a race under normal conditions due to the weather.

Operating above freezing temperatures

Organizers and piste operators have used a variety of options to provide artificial snow for their slopes and cross-country ski trails for decades. However, it is often expensive to get or produce artificial snow, and it is restricted to certain conditions.

“Producing snow using snow cannons, for example, only works if the ratio between outside temperature and humidity – known as the wet-bulb temperature – is within a certain range,” said Tobias Heier, product manager at KTI-Plersch Kältetechnik. “Depending on the humidity, the ambient temperature must be around the freezing point or even well below that if the humidity is high.”

However, such conditions rarely exist during the transition between seasons when many winter sports enthusiasts are hoping to squeeze in their first or last runs of the season on the not-too-crowded pistes, or when international competitions need to run into March and April. Therefore, some organizers have snow delivered from snowy regions and then store it in tents or halls. This approach incurs high logistical and financial costs – not to mention the high carbon dioxide (CO₂) pollution caused by transport, storage and cooling.

The snowPRO all-weather snow systems from KTI offer a solution – even in tropical temperatures

The family-run company KTI-Plersch Kältetechnik chose a different approach, applying its experience developing and implementing industrial refrigeration systems for cooling food or concrete to produce snow systems for ski slopes and cross-country ski trails.

KTI-Plersch increasingly relies on the use of natural refrigerants, which have a positive effect on the environment and on the energy efficiency of its snow systems. The company is now using its years of experience with CO₂-neutral refrigerants for snow production. These refrigerants can be used to produce ice in an environmentally friendly and highly efficient way. The ice is then processed into artificial snow and transported outside using compressed air. This simple principle is combined with the shipping container size of the KTI systems to create snowPRO.

“Our snow has the advantage of a low surface-to-volume ratio, so it retains the cold well,” Heier said. “This means the snow survives longer even at higher temperatures and melts more slowly than ordinary artificial snow from snow cannons.”

Snow can be produced in summer-like temperatures thanks to the weather-independent refrigeration machine. The specially adapted snowPRO system from KTI-Plersch can reliably produce snow at tropical temperatures or an ambient temperature of up to 95°F (35°C).

71 systems in operation worldwide since market launch in 2013

Since the development of the first KTI-Plersch machine for snowmaking at positive temperatures, more than 70 systems have gone into operation worldwide at various altitudes and climatic zones, including downhill ski slopes, biathlon arenas and winter sports training centers in various low mountain ranges in Europe, Oceania, and North America. The systems are also used in indoor ski halls in Thailand and Indonesia to supplement snow cannons. This enables residents to enjoy skiing even when the temperatures outside are tropical.

Organizers and piste operators have used a variety of options to provide artificial snow for their slopes and cross-country ski trails for decades.

In addition, KTI-Plersch rents out the systems for special events and sporting events such as races or ski jumping. All the system requires to operate is a solid foundation and suitable electricity and water connections.

Customized snow technologies ensure high efficiency

KTI-Plersch installs all its systems in a shipping container. This means that the refrigeration units are easily transported to the site and quickly put into operation.

One or more 40-foot containers are used depending on how much snow is needed. A single 40-foot container can produce at least 100 cubic meters (m³) of snow per day. That increases to 210 m³ when two containers are used. However, in the future KTI-Plersch will offer compact systems with a daily capacity of 70 m³ in 20-foot containers.

“These compact snow systems are quick and easy to transport and install, so they can be placed in harder-to-reach places. These types of systems are also ideal for renting out for special events,” said Caroline Walleter-Plersch, CEO of KTI-Plersch. This is where “flake ice” is produced. The water freezes on the inside of a cylindrical ice maker and is removed by a rotating blade roller. The flake ice is then conveyed into the environment by an air stream and crushed to form small ice particles.

Since 2021, variants with an even higher power density of up to 320 m³ per day have been available. These are based on a different type of ice production in which slab ice is produced in an even more energy-efficient manner. KTI-Plersch implemented the idea of using slab ice in technical snowmaking with ski lift operator Florian Leber from Germany’s Winterberg. The first prototype was successfully tested in the winter of 2020–21 on one of its ski slopes.

“Slab ice has surpassed even my most optimistic expectations as an operator of such a system. Residual moisture also allows me to prepare steep sections on frosty nights, as that is when the ice binds very well,” said Leber. “Once the originally coarse structure has been processed with the piste roller, the skier can no longer tell the difference from normal snow. At the same time, the snow is very resistant to solar radiation on the south-facing slope. This system produces about 30 percent more ice – consuming a similar amount of power consumption and using the same installation space – than the flake ice machines that I have been using for several years on the neighboring slope.”

Depending on the slope, the period of time during which snow is produced and personal preferences, ski area operators can choose the right combination of flake ice and slab ice. The integrated pneumatic conveying unit means the snow can be blown up to 450 meters irrespective of the technology.

Snow for every requirement

Regardless of the technology used to produce the snow, consistency plays a vital role for piste operators as well as for professional athletes and their ski technicians. KTI-Plersch systems offer benefits here too.

“Our snow is usually somewhat denser than the snow from ordinary snow cannons,” Heier said. “This means it stays put and doesn’t blow away so easily, meaning that less snow is needed to adequately prepare the slope.”

Several operators also reported that the snow makes the slope faster than slopes prepared with ordinary technical snow from lances or propeller machines, which is advantageous for ski technicians and athletes. In general, thanks to some improvements since the systems launched in 2013, the snow can now be made even more precisely to the desired consistency and small, dry and wetter particles can all be produced to suit many condition requirements. This means that KTI-Plersch has adapted well to the needs of operators of ski slopes and winter sports centers.

“Piste operators don’t have to resort to just looking anxiously at the sky every day and waiting for the first snowflakes to fall. They can now easily and efficiently take effective action to be able to operate pistes beyond the peak season or to confidently stage events, completely independent of the prevailing ambient temperature,” Walleter-Plersch said. 

Further information is available at www.kti-plersch.com.